Display device

Abstract

A display device includes a display panel having a plurality of sub-pixels to display an image; a data driver for supplying image data to the plurality of sub-pixels; a gate driver for supplying a gate signal to the plurality of sub-pixels; a controller configured to convert a driving frequency of each of the data driver and the gate driver in a high frame rate mode; and a gamma voltage generator for generating gamma voltages respectively based on each driving frequency, wherein the controller is configured to generate a horizontal synchronization signal based on the driving frequency in the high frame rate mode. Accordingly, even when the driving frequency conversion occurs, image quality levels corresponding to various driving frequencies respectively may be kept uniform by applying the same operation duration to the various driving frequencies.

What is claimed is: 
     
       1. A display device comprising:
 a frequency converter configured to generate an intermediate frequency between a first driving frequency and a second driving frequency when a driving frequency of the display device is changed from the first driving frequency to the second driving frequency; and 
 an intermediate voltage generator configured to generate intermediate voltages corresponding to the intermediate frequency based on each of the first driving frequency and the second driving frequency, 
 wherein an intermediate voltage corresponding to the intermediate frequency is a value interpolated between a first voltage corresponding to the first driving frequency and a second voltage corresponding to the second driving frequency, and 
 wherein when the driving frequency of the display device is changed from the first driving frequency to the second driving frequency, the display device sequentially operates at the first driving frequency, the intermediate frequency, and the second driving frequency. 
 
     
     
       2. The display device of  claim 1 , wherein the second driving frequency is greater than the first driving frequency, and
 wherein each of a gate driver and a data driver is configured to operate at the first driving frequency using a horizontal synchronization signal generated based on the second driving frequency. 
 
     
     
       3. The display device of  claim 2 , wherein a sub-pixel has a same operation duration at the first driving frequency and the second driving frequency. 
     
     
       4. The display device of  claim 1 , wherein the intermediate voltage generator is further configured to obtain the intermediate voltage corresponding to the intermediate frequency by:
 dividing a difference between the first driving frequency and a first intermediate driving frequency by a difference between the first driving frequency and the second driving frequency to obtain a compensation coefficient; and 
 applying the compensation coefficient to the second voltage to obtain an interpolated voltage, wherein the interpolated voltage is the intermediate voltage corresponding to the intermediate frequency. 
 
     
     
       5. The display device of  claim 4 , wherein the compensation coefficient is preset rather than calculated based on the driving frequency. 
     
     
       6. The display device of  claim 1 , wherein the intermediate voltage generator includes an intermediate voltage setter, an interpolated voltage setter, and an intermediate voltage selector. 
     
     
       7. The display device of  claim 6 , wherein the intermediate voltage setter includes a first memory and a first selector,
 wherein the first memory stores a plurality of intermediate voltage sets corresponding to a plurality of driving frequencies, 
 wherein the first selector selects and outputs one of the plurality of intermediate voltage sets based on a driving frequency selection signal. 
 
     
     
       8. The display device of  claim 7 , wherein the interpolated voltage setter includes an intermediate voltage interpolator, a second memory, and a second selector,
 wherein the intermediate voltage interpolator generates an interpolated voltage set corresponding to the intermediate frequency using a plurality of gamma voltage sets stored in the intermediate voltage setter. 
 
     
     
       9. The display device of  claim 8 , wherein the intermediate voltage selector is configured to:
 select and output the intermediate voltage from the intermediate voltage set based on a driving frequency conversion signal. 
 
     
     
       10. The display device of  claim 1 , wherein a controller is configured to convert RGB image data received from an external host system to RGBG image data and then output the RGB G image data. 
     
     
       11. A display device comprising:
 a display panel on which a plurality of pixels are disposed to display an image; 
 a data driver configured to supply image data to the plurality of pixels; and 
 a controller configured to determine a driving frequency of the data driver in units of frames; 
 wherein the driving frequency includes a first frequency a second frequency, and an intermediate frequency between the first frequency and the second frequency, 
 wherein when the first frequency is changed from the first frequency to the second frequency, the data driver operates at an intermediate frequency in at least some frames from the frames and sequentially operates at the first frequency, the intermediate frequency, and the second frequency, and 
 wherein the image data is generated by interpolation at the intermediate frequency in the at least some frames. 
 
     
     
       12. The display device of  claim 11 , further comprising:
 a voltage generator configured to generate a voltage corresponding to the driving frequency and an intermediate voltage corresponding to the intermediate frequency. 
 
     
     
       13. The display device of  claim 12 , wherein the voltage generator is configured to obtain the intermediate voltage by:
 dividing a difference between the first frequency and the intermediate frequency by a difference between the first frequency and the second frequency to obtain a compensation coefficient; and 
 applying the compensation coefficient to a voltage corresponding to the second frequency to obtain an interpolated voltage, wherein the interpolated voltage is the intermediate voltage. 
 
     
     
       14. The display device of  claim 12 , wherein the intermediate voltage is selected from an intermediate voltage set, and
 wherein the voltage generator configured to generate the intermediate voltage set based on a pre-stored voltage set corresponding to the first frequency and the second frequency. 
 
     
     
       15. The display device of  claim 12 , wherein the voltage generator is configured to generate the intermediate voltage based on a value interpolated between a first voltage corresponding to the first frequency and a second voltage corresponding to the second frequency. 
     
     
       16. The display device of  claim 11 , further comprising:
 a light-emitting element configured to emit light using a driving current; and 
 a driving transistor configured to control the driving current to be applied to the light-emitting element. 
 
     
     
       17. The display device of  claim 16 , further comprising:
 a first transistor connected to a first node of the driving transistor and a second node of the driving transistor; 
 a second transistor connected to a data line and a fourth node of the driving transistor; 
 a third transistor connected to the fourth node of the driving transistor and an input of a high-level driving voltage; 
 a fourth transistor connected to the second node of the driving transistor and a third node of the light-emitting element; 
 a fifth transistor connected to the first node of the driving transistor and an input of an initialization voltage; 
 a sixth transistor connected to the input of an initialization voltage and the third node of the light-emitting element; and 
 a capacitor connected to the first node of the driving transistor and the input of the initialization voltage. 
 
     
     
       18. The display device of  claim 17 , wherein an anode electrode of the light-emitting element is connected to the third node of the light-emitting element,
 wherein a cathode electrode of the light-emitting element is connected to an input of a low-level driving voltage, and 
 wherein a multilayer-based organic compound stack is formed between the anode electrode and the cathode electrode. 
 
     
     
       19. The display device of  claim 18 , wherein the multilayer-based organic compound stack includes a hole transfer layer, an electron transfer layer, and a light-emitting layer, and
 wherein the hole transfer layer includes a hole injection layer, a hole transport layer, and an electron blocking layer, and 
 wherein the electron transfer layer includes an electron transport layer, an electron injection layer, and a hole blocking layer. 
 
     
     
       20. The display device of  claim 11 , wherein the data driver includes at least one source driver integrated circuit to drive a plurality of data lines, and
 wherein each of the source driver integrated circuit includes a logic unit including a shift register, a latch circuit, a digital analog converter (DAC), and an output buffer.